CVE-2021-21403

Q: How do I fix CVE-2021-21403?

Upgrade kongchuanhujiao to 1.3.21 or later.

Q: Is CVE-2021-21403 being actively exploited?

Not that we know of. CVE-2021-21403 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 1.4% is the estimated probability that it will be exploited in the next 30 days. That is higher than 69% of all scored CVEs.

Q: How severe is CVE-2021-21403?

CVE-2021-21403 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

Q: What does CVE-2021-21403 affect?

Published advisories record a fix for kongchuanhujiao (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

HIGH

7.5

CVSS v3

NVD

Description

In github.com/kongchuanhujiao/server before version 1.3.21 there is an authentication Bypass by Primary Weakness vulnerability. All users are impacted. This is fixed in version 1.3.21.

CWE-305 CWE-287Improper Authentication

How to fix

Remediation Available

kongchuanhujiaoNVD

Affected:< 1.3.21Fixed in:1.3.21CVE-2021-21403derived from NVD

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityNone

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Exploit Intelligence

1.36%probability of exploitation in 30 days

69thpercentile

Moderate risk: more likely to be exploited than 69% of all known CVEs.

References

Patch1

github.com

Third-Party Advisory1

github.com

Related Vulnerabilities

Other CWE-305 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2025-31161	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2020-10923	High	8.8	85%	-	-
CVE-2023-28126	Medium	5.9	67%	-	-
CVE-2023-34124	Critical	9.8	46%	-	Fix
CVE-2025-32011	Critical	9.8	27%	-	-
CVE-2024-37085	Medium	6.8	26%	KEV + Ransom	Fix

Common questions

How do I fix CVE-2021-21403?

Upgrade kongchuanhujiao to 1.3.21 or later.

Is CVE-2021-21403 being actively exploited?

Not that we know of. CVE-2021-21403 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 1.4% is the estimated probability that it will be exploited in the next 30 days. That is higher than 69% of all scored CVEs.

How severe is CVE-2021-21403?

CVE-2021-21403 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2021-21403 affect?

Published advisories record a fix for kongchuanhujiao (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2021-21403

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.